Background: Pupillary observation in the dark is always a problem in a general ophthalmological practice or an outpatient clinic without specialized equipment. We present two methods for observation of the pupils in darkness: 1) illumination of the pupils with the skiascope as a routine examination and 2) infrared observation of the pupils with a consumer digital video camera.
Methods: (1) Pupillary reactions are observed with the skiascope/retinoscope, the observation beam of the device focused to infinity and documented with a video camera. (2) Infrared observation of the pupils was performed with a digital consumer video camera, allowing observation of the pupillary reaction in darkness. After recording, video sequences of interest were transferred to a personal computer and the still images of interest extracted.
Results: In everyday clinical routine, observation of the pupillary reaction with the skiascope/retinoscope proves as a reliable tool with a large bandwidth of illumination and a high contrast between pupil and surrounding area. The infrared video camera allows an excellent visualization of the pupillary reflex in darkness. The transfer of the video sequences to a personal computer proved to be simple and single images can easily be chosen.
Conclusion: Observation of the pupillary reflex with the skiascope proved a useful tool that is available in practically every ophthalmological office. Use of the infrared digital consumer video camera (available at low prices) is a highly sophisticated tool for observation and documentation of pupillary reflex in darkness.